Watch comprising an electronic information-storage unit in the base of the case thereof

ABSTRACT

The invention relates to watches, generally wristwatches, whose cases incorporate electronic modules for storing information that comprise an integrated circuit connected to an antenna consisting of a coil and are able to communicate by radio signals with a reading and/or writing device adapted at least to read the information contained in a memory of the integrated circuit and often also adapted to delete or modify at least some of that information and to add other information.  
     To eliminate the drawbacks of prior art watches in which the module is inside the case (complicated fabrication or new design of the watch, increased volume thereof) or to reduce the importance of those drawbacks (attenuation and/or distortion of the signals sent and received by the coil), in the watch of the invention the electronic module ( 14 ) is housed at least for the most part in a cavity ( 13 ) in the back ( 3 ) of the case ( 1 ) open towards the outside.

The present invention relates to watches, generally wristwatches, whosecases incorporate electronic modules for storing information thatcomprise an integrated circuit or chip connected to an antennaconsisting of a coil and are able to communicate by radio signals with areading and/or writing device adapted at least to read the informationcontained in a memory of the integrated circuit and often also adaptedto delete or modify at least some of that information and to add otherinformation.

To be more precise, the invention relates to watches in which theelectronic modules are passive, meaning that these modules do not needtheir own power supply, such as batteries or rechargeable batteries, tobe able to operate, being supplied with power by the radio signals fromthe reading and/or writing device with which they co-operate.

Some watches of the above kind merely store an access code to private orprotected premises or to ski slopes, for example. Others includeelectronic modules equipped with more complicated integrated circuitsand may contain the medical records of their owner.

In some prior art watches, the electronic module is placed in a hollowand preferably removable bezel so that the module can be changed ifnecessary. This solution may therefore not be suitable for watcheshaving any type of case. Moreover, if the case actually includes a bezelor a case-bezel, this complicates its fabrication and consequentlyincreases the unit cost of the watch.

The document JP 2000-339503 describes a watch of the above kind thatcomprises an electronic module mounted on the outside of the watchglass. One drawback of placing said module on the glass is that itcannot be protected from mechanical shock when the user is wearing thewatch. Also, as it is in front of the watch dial, it is always visible,which degrades the aesthetics of the watch.

In other watches the module is placed in a space between the rear of themovement of the watch and the back of the case, which necessarilyincreases their volume. If the back of the case is made from a materialthat is not really amagnetic, such as steel, the magnetic flux emittedor received by the coil of the electronic module suffers high losses,and even if measures are taken to limit these losses, they are far fromnegligible. Finally, even if the back of the case is made from anamagnetic material, for example a plastic material, radio signalsemitted and received by the coil of the module, which have to passthrough the whole of the thickness of the back, suffer high attenuation.

The object of the invention is to provide a watch, in particular awristwatch, that completely eliminates or at least reduces the drawbacksof the above prior art watches.

To achieve the above object, the watch has the features set out in claim1.

Advantageous embodiments of the watch are defined in the dependentclaims 2 to 8.

The cavity and the module preferably have an essentially cylindricalshape and are preferably situated at the centre of the back of the case.

Accordingly, unlike a watch in which the module is placed at the back ofthe case and entirely within it, in the watch of the invention signalsemitted and received by the coil of the module have to pass only throughthe base of the module, which is much thinner than the back of the case.

It is possible to obtain a watch of the invention starting with anexisting watch by forming in its back a blind hole with a shape adaptedto that of the electronic module.

If the back of the case is removable, it is possible to replace it toconvert an ordinary watch into a watch of the invention.

This being so, in one embodiment of the watch of the invention, the baseof the module is cup-shaped and has a flat bottom to which the coil andthe integrated circuit are fixed and a lateral wall around the coil.

This embodiment is particularly suitable if the back of the case is madefrom a magnetic material such as steel.

The invention will be better understood after reading the followingdescription, which is given by way of example and with reference to theappended drawings, of several embodiments of the invention, in whichdrawings:

FIG. 1 is a diagrammatic view in diametral section of an analoguedisplay wristwatch of the invention;

FIG. 2 is a view in diametral section to a larger scale of the portionof the back of the FIG. 1 case which accommodates a first embodiment ofan electronic module incorporated into the back;

FIG. 3 is an incomplete plan view of the electronic module shown in FIG.2, showing how the ends of the wire of its coil are connected torespective terminals of the integrated circuit of the module;

FIG. 4 is a view in section analogous to that of FIG. 2 of a secondembodiment in which the ends of the wire of the coil of the electronicmodule are connected in a different way to the terminals of itsintegrated circuit;

FIG. 5 is a view analogous to that of FIG. 3 for the FIG. 4 mode ofconnecting the integrated circuit and the coil; and

FIGS. 6 and 7 are views analogous to that of FIG. 2 showing otherembodiments of electronic modules that can be incorporated into the backof a watch case of the invention.

Although the invention is obviously not limited to this application, thefollowing description applies to the situation in which the electronicmodule fitted to the watch is designed to store information that relatesto the watch itself and to be placed at a very small distance (a fewmillimetres at the most) from the coil that constitutes the send andreceive antenna of a reading and/or writing device with which it is ableto communicate.

The wristwatch shown diagrammatically in FIG. 1 comprises a case 1 thatconsists of a metal case-bezel unit 2, a metal back 3 and a glass 4clamped to the case-bezel unit 2 in the conventional way by means of agasket 5 which also seals the glass to the case.

FIG. 1 shows the back 3 clipped to the case-bezel unit 2, but the backcould equally well be screwed to it or fixed to it by means of a bayonetsystem in such a manner as to compress a gasket 5′ that seals the backto the case.

The case 1 finally comprises a wrist-band attachment system that is notvisible in FIG. 1 and may comprise two pairs of horns on the case-bezelunit 2.

The case 1 houses a movement 6 which drives a minute hand 8 and an hourhand 9 placed in front of a dial 7 and which comprises a control spindle10 that passes through the case-bezel unit 2 and terminates in a crown11, an O-ring 12 sealing the case 1 where the spindle passes through thecase-bezel. If the watch is not of the electromechanical or self-windingtype, the spindle 10 and the crown 11 are also used to wind the watch.

In accordance with the invention, the back 3 of the case 1 has a cavity13 that is open towards the exterior of the case and houses anelectronic module 14, the cavity and the module preferably beingessentially cylindrical and situated at the centre of the back 3.

Given that, in the application envisaged here, the electronic module 14has a much smaller area than the back of the case and the module can bemade in various shapes, it is merely represented in FIG. 1 by arectangle.

FIG. 2 is a view in section to a larger scale of part of the back 3 ofthe case 1 from FIG. 1 and shows one embodiment of the electronic module14 that is adapted to be inserted permanently into the cavity 13 in theback.

In this embodiment, the module 14 comprises a base 15 made from anamagnetic and electrically insulative material. This material may be aplastic material such as high-density polyethylene or a ceramicmaterial, for example, plastic materials being reserved for bottom ofthe range watches and middle of the range watches and ceramic materialsfor top of the range watches. In the latter case the ceramic materialpreferably has substantially the same colour and the same appearance asthe metal that constitutes the back of the case, unless a particularaesthetic effect is required.

As shown in FIG. 2, the base 15 is cup-shaped and has a flat bottom 16and an essentially cylindrical lateral wall 17. This figure also showsthat the thickness of the wall 17 increases slightly and continuouslyfrom its base to its top so that its exterior surface 18 has aparticular shape enabling it to co-operate with the internal wall 19 ofthe cavity 13, which has a complementary shape, to constitute a dovetailjoint.

The external edge 20 of the wall 17 of the base and the rim 21 of thewall 19 of the cavity 13 are rounded to facilitate insertion of themodule 14 into the cavity.

FIG. 3 is a plan view of the electronic module 14 from FIG. 2 without anadhesive filler material referred to hereinafter.

Referring to FIGS. 2 and 3, it can be seen that the lateral wall 17 ofthe base 15 has a truly cylindrical internal surface 22 which surroundsa flat and self-supporting annular coil 23, to be more precise acylindrical coil. In the manner known in the art, the coil consists of aplurality of layers of contiguous and coaxial turns, not visible in thedrawing, made from a very thin metal wire 28, preferably copper wire,covered with a sheath or an insulative and thermo-adhesive material thatis partially melted by heating it so that all the portions of the sheaththat surround the turns of wire are welded together when the coil isallowed to cool afterwards.

The coil 23 itself surrounds an integrated circuit 24 smaller thanitself, of rectangular parallelepiped shape, and which has on its frontface 25 two connecting terminals or “bumps” 26 and 27 to which the twoends 29 of the metal wire of the coil 23 are welded or fixed by means ofa conductive adhesive.

The two connecting terminals 26 and 27 of the integrated circuit 24shown in FIGS. 2 and 3 are disposed opposite each other in thelengthwise direction of the integrated circuit 24, but it is clear thatthey could be otherwise disposed on the front surface of the integratedcircuit, for example side by side in its widthwise direction.

In this first embodiment, the coil 23 and the integrated circuit 24 arefixed directly to the internal face 30 of the flat bottom 16 of the base15 by means of a thin layer of adhesive material 31 (see FIG. 2) and thespace inside the coil left free by the integrated circuit is filled withan adhesive and insulative thermosetting material 32, for example anepoxy resin, to protect the ends 29 of the wire of the coil 23 and themeans fixing them to the connecting terminals 26 and 27 before themodule 14 is incorporated into the back of the watch case. The adhesivematerial 32 is preferably opaque so that it also protects the integratedcircuit against light before it is incorporated into the back of thewatch case.

The base 15 has or may have three functions.

Firstly, if the back 3 of the case 1 is made from a magnetic material,for example steel, this amagnetic material base serves as a screenbetween the back and the coil, to eliminate, if not totally, at leastthe majority of the magnetic flux losses in the back 3 when the coilsends and receives radio signals respectively to and from a readingand/or writing device to which it may be coupled.

Secondly, as shown in FIG. 2, the module 14 projects slightly from theexternal face 33 of the back 3 of the case 1 to form a boss 34 adaptedto position it optimally and quickly on a head 35 of a reading and/orwriting device shown partly and diagrammatically in dashed outline inFIG. 2 and which itself comprises an antenna 36 in the form of a coil.This head, which incorporates a recess 35′ whose shape and dimensionscorrespond to those of the boss 34, may be connected via an interface toa device specifically designed to communicate with the memory of thewatch, preferably a fixed or portable personal computer (PC).

Obviously, the boss 34 of the module would enable the watch to be placedin the same way on any support having a recess corresponding to theshape and dimensions of the boss.

If the module projects from the back of the case 1, its external edge 37is preferably rounded to prevent the boss 34 causing discomfort to thewearer of the watch.

In all cases, it is clear that, because radio waves emitted and receivedby the coil 23 of the module 14 no longer have to pass through the wholeof the thickness of the back 3 of the case 1 of the watch, but only thatof the bottom 16 of the base of the module, which is much thinner, theseradio waves will be much less attenuated and distorted than in prior artwatches in which the electronic module is placed at the bottom butinside the case.

Until now, only one memory has been referred to in relation to theintegrated circuit 24. It is nevertheless clear that this circuit couldcomprise a plurality of memories of different types, in particularmemories for storing information that can only be read and othermemories for storing other information that can also be deleted and/ormodified or have additional information added to it.

This is the situation in the application example previously referred toin which the electronic module stores information relating to the watchitself, to be more precise its source, its purchaser and, just like acar, its “service record”; this information personalises the watch,which may be of benefit on selling the watch or facilitate the task of awatchmaker if the watch is passed to him for inspection or repair orsimply for him to change the battery if the watch is of theelectromechanical or electronic type.

In the case of middle of the range and top of the range watches, thestored information may be divided into the following four categories,for example:

-   -   1—“Brand” and model name or number under which the watch was        sold, and where applicable a code specific to the brand, and a        date on which and an address to which the watch was shipped to a        retailer.    -   2—“Plant”: name or sign of the company having manufactured the        watch movement if this is not the same as the company selling        the watch, and internal designation of the movement.    -   3—“Point of sale”: retailer name and address, date of purchase        and name of purchaser.    -   4—“Customer services”: some or all of the above information,        plus the date of and information on servicing carried out by the        vendor or another retailer (for example adjustment, testing,        battery replacement) and in the latter case the name and address        of the other retailer.

Some of the above information may be stored in a ROM memory so that itcan only be read. This applies to the “Brand” and “Plant” informationreferred to above.

The other information (“Point of sale”, “Customer services”) may bestored in one or more dynamic RAM, EPROM or EEPROM memory so that it canbe deleted, modified or added to, if necessary.

The stored information depends also on the type of watch in whose casethe electronic module is incorporated. For example, in the case of abottom of the range watch whose case is of one-piece construction with awelded-on glass that prevents all possibility of working inside thewatch, with the possible exception of changing the battery or having thebattery changed if the watch is of the electromechanical or digital kindand under warranty, just the “Brand” and “Plant” information may bestored in read-only memory.

In all cases, the coil of a read head or of a support may be connectedvia an appropriate interface to a fixed or portable computer able toread the information contained in the memory or memories of the moduleand where applicable to delete, modify and add to some of thatinformation.

This information may be sent to a protected Internet site or over anIntranet loop to which all persons involved with the watch have access.

FIGS. 4 and 5 are analogous to FIGS. 2 and 3 and show a secondembodiment of the electronic module of a watch of the invention. Inthese figures, the same and corresponding components are designated bythe same reference numbers, and only new components are indicated by newreference numbers.

One of the differences between the embodiment of FIGS. 4 and 5 and thatof FIGS. 2 and 3 is that the coil 23 and the circuit 24 are no longerstuck directly to the internal face of the bottom 16 of the module 14,but instead to the substrate 38 of a printed circuit 39 which may itselfbe stuck to the bottom 16 of the base 15 of the module 14 or merely setinto the base.

The other difference is that the ends of the wire 29 of the coil 23 nolonger connect the coil to the terminals 26 and 27 of the integratedcircuit 25 directly but instead via connecting lands 40 formed on thesubstrate 38 of the printed circuit 39. To be more precise, each end ofthe wire 29 is welded or stuck by means of an electrically conductiveadhesive to one of the lands 40 which is in turn connected to aconnecting terminal 26 or 27 of the integrated circuit 24 by aconductive wire 41.

Thanks to this the coil 23 and the integrated circuit 24 can beelectrically connected using the standard automated wire bonding method.

In the embodiment shown in section in FIG. 6, the exterior surface 18 ofthe lateral wall 17 of the base 15 and the internal wall 19 of thecavity 13 in the back 3 of the watch case are both true cylinders andthe module 14 is set into the cavity or adhesively bonded to theinterior of the cavity. The external edge 21 of the wall 17 and that ofthe module 14 are not rounded as in the embodiment of FIGS. 2 and 3, butright-angled.

This embodiment is more suitable if the back 3 of the case and/or thebase 15 of the module 14 are made from very hard materials that aredifficult to machine or shape, such as certain ceramic materials orsapphire.

In this embodiment, as in that of FIGS. 2 and 3, the ends of the wire ofthe coil 23 are fixed directly to the connecting terminals 26 and 27 ofthe integrated circuit 24, but it is obvious that these ends of the wireand these terminals 26 and 27 could be connected in the same way as inthe embodiment of FIGS. 4 and 5.

Note that in a different embodiment, not shown in the drawings, themodule 14 could be crimped into the cavity 13 in the back 3 of the case.The base 15 of the module would then have on the same side as its bottom16 an external peripheral cut-out in which an internal rim of the back 3would engage. This method of fixing the module could be used if it werenot possible to set it into the case or adhesively bond it to the case,for example.

Unlike the FIG. 6 embodiment, which is reserved for top of the rangewatches, that shown in section in FIG. 7, which is much simpler and moreeconomical, is very suitable for bottom of the range watches in whichthe back is made from a plastic material, for example.

In this case, the base 15 is reduced to a simple rigid plate of the samediameter as the outside diameter of the coil 23, and which may be madefrom the same material as the back of the case, in which eventuality themodule 14 may be set into or adhesively bonded in the cavity 13 in theback of the case.

The above remarks as to the connection between the ends of the wire ofthe coil and the terminals of the integrated circuit are equally validfor this embodiment.

Clearly the invention is not limited to the embodiments or variants thathave just been described or envisaged.

For example, instead of connecting the ends of the wire of the coil tothe terminals of the integrated circuit by means of connecting landsusing the wire bonding technique, this connection could be obtainedusing another well-known automated technique known as tape automatedbonding (TAB), which is described in European Patent No. 0 376 062.

Although the method is described in that patent for producing electronicmodules intended to be incorporated totally into electronic keys orcards, it is very suitable for producing modules to be fitted to watchesof the invention.

In all the embodiments described or envisaged hereinabove, the back ofthe electronic module is proud of the exterior surface of the back ofthe case of the watch, but this is not obligatory.

In these embodiments and variants, the electronic module is fixedpermanently into the cavity in the back of the case, but it would beentirely feasible to design a module with a base provided with a lateralwall enabling it to co-operate with an internal wall of the cavity inthe back so as to render the module removable, and where applicableinterchangeable, for example by means of a screwing or bayonet fixingsystem.

In this eventuality, it would obviously be necessary to provide meansfor extracting the module from the cavity in the back of the case andreplacing the same module or substituting a replacement module. Thosemeans could be a groove in the exterior face of the module, for example,like those provided for battery compartment covers in electromechanicalor electronic watches.

Finally, another option would be to modify the characteristics of theantenna coil, in particular its diameter and the number of turns, toenable it to communicate with the antenna of a reading and/or writingdevice not at a distance of a few millimetres but at a distance of a fewcentimetres or tens of centimetres.

1. A watch comprising a case having a back, a movement contained in saidcase and an electronic module for storing information able tocommunicate by radio signals with a device for reading and/or writingsaid information, said module comprising a cup-shaped amagnetic materialbase, an integrated circuit having at least two connecting terminals andfixed to a flat bottom of said base and a send and receive antennacomprising a coil also fixed to to the flat bottom of said base andsurrounded by a lateral wall of said base, the coil consisting of anelectrically conductive wire having two ends connected to respectiveconnecting terminals of said integrated circuit, said coil having anannular shape and surrounding a space in which said integrated circuitis placed, wherein said electronic module is housed at least for themost part in a cavity in the back of the case open towards the outside,and wherein the thickness of said lateral wall increases slightly andcontinuously from its base adjoining said flat bottom to its top so thatit has an exterior surface co-operating with an internal wall ofcomplementary shape of said cavity and constitutes a dovetail jointbetween said electronic module and the back of said case.
 2. The watchaccording to claim 1, wherein said cavity and said module have anessentially cylindrical shape and are situated at the centre of the backof said case.
 3. The watch according to claim 1, wherein the base ofsaid module is set into, adhesively bonded in or crimped in said cavity.4. The watch according to claim 1, wherein said base is made of aplastic material, a ceramic material or sapphire.
 5. The watch accordingto claim 1, wherein said coil is a self-supporting coil that comprises aplurality of layers of contiguous and substantially coaxial turns thatare formed by a thin metal wire surrounded by a sheath of electricallyinsulative material and connected together.
 6. The watch according toclaim 1, wherein said coil and said integrated circuit are adhesivelybonded directly to said base and said ends of the wire of the coil arealso fixed directly to said terminals of the integrated circuit by meansof an electrically conductive material.
 7. The watch according to claim1, wherein said coil and said integrated circuit are fixed to thesubstrate of a printed circuit that has two connecting lands situatedbetween said coil and said integrated circuit to which are fixed saidends of the wire of said coil and two ends of two conductive wires whoseother ends are fixed to said connecting terminals of said integratedcircuit.
 8. The watch according to claim 1, wherein said module has aportion projecting out of the back of said case adapted to position itquickly and accurately on a head of said reading and/or writing devicewhich itself comprises an antenna in the form of a coil and has a recesssubstantially the same shape and size as said boss.